US GENERAL-AVIATION autopilot specialist S-TEC, has introduced its first helicopter stability- and control-augmentation system (SCAS). The system will become available for the Bell 206L-4 LongRanger in the third quarter of 1996 and approval for other airframes will follow, the Mineral Wells, Texas-based company says.
S-TEC says that the basic SCAS improves control harmony and reduces outside disturbances to reduce pilot workload, and consists of the first component of a modular helicopter-flight-control system. The system is full-time, operating throughout the flight envelope, with the servos acting in series with the pilot inputs.
The SCAS will be upgradable to a full flight-control system, S-TEC says. Options will include a force-trim system, which will restrain cyclic control for short periods, to enable the pilot to accomplish other cockpit tasks.
Growth to a visual-flight-rules (VFR) flight-control system will require conversion of the series-servo force-trim system to full-authority parallel-trim actuators, and the addition of attitude and airspeed transducers and an autopilot circuit-card.
Source: Flight International
